leer Ansicht nicht angezeigt wird in Listenansicht

Question

ich leer Ansicht Anzeige versuchen, wenn keine Internetverbindung mir keine Internetverbindung geben und kein Buch angezeigt wird, wenn kein Buch nicht

gefunden Dies ist mein Code

public class MainActivity extends AppCompatActivity { 
private static final String BOOK_REQUEST_URL = "https://www.googleapis.com/books/v1/volumes?q="; 
public static final String LOG_TAG = MainActivity.class.getName(); 
// search button 
private Button search_button; 
// edit text to use for search 
private EditText editText; 
// string used to get string from edit text. 
private String queryWord = null; 
private TextView emptyTextView; 
private ListView bookListView; 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 
    search_button = (Button) findViewById(R.id.next_button); 
    editText = (EditText) findViewById(R.id.edit_text); 
    emptyTextView = (TextView) findViewById(R.id.empty_view); 

    bookListView = (ListView) findViewById(R.id.list_view); 

    // Get a reference to the ConnectivityManager to check state of network connectivity 
    ConnectivityManager connMgr = (ConnectivityManager) 
      getSystemService(Context.CONNECTIVITY_SERVICE); 

    // Get details on the currently active default data network 
    final NetworkInfo networkInfo = connMgr.getActiveNetworkInfo(); 

hier möchte ich, wenn eine Verbindung nicht geben Sie mir kein Internet connection`

search_button.setOnClickListener(new View.OnClickListener() { 
     @Override 
     public void onClick(View v) { 
      if (networkInfo != null && networkInfo.isConnected()) { 

       new GetBook().execute(BOOK_REQUEST_URL); 
      } else { 

       emptyTextView.setText(R.string.NoConnect); 
       bookListView.setEmptyView(emptyTextView); 

      } 
     } 

    }); 
    new GetBook().execute(BOOK_REQUEST_URL); 
} 
// method to get string from edit text. 
public String getBook() { 
    queryWord = editText.getText().toString(); 
    if (queryWord == null) { 
     bookListView.setEmptyView(emptyTextView); 
    } 
    return queryWord; 
} 

/** 
* Update the UI with the given book information. 
*/ 
private void updateUi(List<Book> books) { 

    // Find a reference to the {@link ListView} in the layout 

    // Create a new {@link ArrayAdapter} of book 
    final BookAdapter adapter = new BookAdapter(this, books); 

    // Set the adapter on the {@link ListView} 
    // so the list can be populated in the user interface 
    bookListView.setAdapter(adapter); 

} 
// inner class for to support methods do in the background. 
private class GetBook extends AsyncTask<String, Void, List<Book>> { 

    @Override 
    protected List<Book> doInBackground(String... urls) { 
     String word_search = getBook(); 
     // Don't perform the request if there are no URLs, or the first URL is null. 
     if (urls.length < 1 || urls[0] == null) { 
      return null; 
     } 
     List<Book> result = QueryUtils.fetchBookName(urls[0], word_search); 
     return result; 
    } 

    /** 
    * This method is invoked on the main UI thread after the background work has been 
    * completed. 
    * <p> 
    * It IS okay to modify the UI within this method. We take the {@link Book} object 
    * (which was returned from the doInBackground() method) and update the views on the screen. 
    */ 

hier möchte ich keine Liste Buch

@Override 
     protected void onPostExecute(List<Book> book) { 

      emptyTextView.setText(R.string.nobook); 
      bookListView.setEmptyView(emptyTextView); 

      // Hide loading indicator because the data has been loaded 
      View loadingIndicator = findViewById(R.id.loading_indicator); 
      loadingIndicator.setVisibility(View.GONE); 
      if ((book != null) && !book.isEmpty()) { 
       updateUi(book); 
      } 

     } 
    } 
} 

ich mehr Schritte nichts

Answer 1

versuchen diese

View emptyV = getActivity().getLayoutInflater().inflate(R.layout.empty_view, null); 
        TextView tvMSG = (TextView) emptyV.findViewById(R.id.tvMSG); 
        tvMSG.setText("No product available."); 
        ViewGroup viewGroup= (ViewGroup) listView.getParent();     
        viewGroup.addView(emptyV, new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, 
          ViewGroup.LayoutParams.MATCH_PARENT)); 
        listView.setEmptyView(emptyV); 

Answer 2

Sie einen anderen layout für empty passieren versuchen anzuzeigen hinzufügen Staat und pragmatisch show/hide abhängig von list Größe. Hier

ein Beispiel:

activity_main.xml

<?xml version="1.0" encoding="utf-8"?> 
<RelativeLayout 
    xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:tools="http://schemas.android.com/tools" 
    xmlns:app="http://schemas.android.com/apk/res-auto" 
    android:id="@+id/container" 
    android:layout_height="match_parent" 
    android:layout_width="match_parent"> 

    <ListView 
     android:id="@+id/list_view" 
     android:layout_width="match_parent" 
     android:layout_height="match_parent" /> 

    <RelativeLayout 
     android:id="@+id/layout_empty" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_centerVertical="true" 
     android:layout_centerHorizontal="true" 
     android:visibility="gone" 
     android:layout_margin="30dp"> 

     <ImageView 
      android:id="@+id/image_empty" 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:layout_centerHorizontal="true" 
      android:src="@mipmap/ic_launcher"/> 

     <TextView 
      android:id="@+id/text_empty" 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:layout_centerHorizontal="true" 
      android:layout_below="@id/image_empty" 
      android:layout_marginTop="16dp" 
      android:gravity="center" 
      android:textSize="20sp" 
      android:textStyle="bold" 
      android:textColor="@color/textColorPrimary" 
      android:text="Oops!"/> 

     <TextView 
      android:id="@+id/text_empty_hints" 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:layout_centerHorizontal="true" 
      android:layout_below="@id/text_empty" 
      android:layout_marginTop="16dp" 
      android:gravity="center" 
      android:textSize="14sp" 
      android:textStyle="bold" 
      android:textColor="@color/textColorSecondary" 
      android:text="No items found"/> 
    </RelativeLayout> 
</RelativeLayout> 

MainActivity.java:

private ListView bookListView; 
private RelativeLayout layoutEmpty; 

....... 
............ 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 

    bookListView = (ListView) findViewById(R.id.list_view); 
    layoutEmpty = (RelativeLayout) findViewById(R.id.layout_empty); 

    ....... 
    ........... 
} 

private void updateUi(List<Book> books) { 

    if(books.size() > 0) { 
     layoutEmpty.setVisibility(View.GONE); 
     bookListView.setVisibility(View.VISIBLE); 
    } else { 
     layoutEmpty.setVisibility(View.VISIBLE); 
     bookListView.setVisibility(View.GONE); 
    } 
} 

OUTPUT:

Hope this helfen ~